Window Object in Javascript: Properties and Methods

1 The Window object is the top level object and represents the window of the browser.

2. Window objects are either the current window (if the browser is displaying only a single document), or those created with a window.open() method (where the name is specified in the code), or separate frames, if the document is laid out using a <FRAMESET> definition (where the windows are named in the <FRAME> element).

3. As the Window object is the top level object in the object hierarchy and the existance of the current window is assumed, most Window properties need not be prefixed by Window. For example, the following two references are identical :

window.defaultStatus
defaultStatus

and would both return the default text of the status bar for the current window.

4. Difference between Window and Documnet Objects:

Window is the first thing that gets loaded into the browser. The document object is your html document that will be loaded into the browser. The Document object provides access to all HTML elements in a page, from within a script. The document actually gets loaded inside the window object. The Document object is a part of the Window object, and can be accessed through the window.document property.

Window Objecy Properties

closed: Returns a Boolean value indicating whether a window has been closed or not
defaultStatus: Sets or returns the default text in the statusbar of a window
document: Returns the Document object for the window
frames: Returns an array of all the frames (including iframes) in the current window
history: Returns the History object for the window
innerHeight: Sets or returns the inner height of a window's content area
innerWidth: Sets or returns the inner width of a window's content area
length: Returns the number of frames (including iframes) in a window
location: Returns the Location object for the window
name: Sets or returns the name of a window
navigator: Returns the Navigator object for the window
opener: Returns a reference to the window that created the window
outerHeight: Sets or returns the outer height of a window, including toolbars/scrollbars
outerWidth: Sets or returns the outer width of a window, including toolbars/scrollbars
pageXOffset: Returns the pixels the current document has been scrolled (horizontally) from the upper left corner of the window
pageYOffset: Returns the pixels the current document has been scrolled (vertically) from the upper left corner of the window
parent: Returns the parent window of the current window
screen: Returns the Screen object for the window
screenLeft: Returns the x coordinate of the window relative to the screen
screenTop: Returns the y coordinate of the window relative to the screen
screenX: Returns the x coordinate of the window relative to the screen
screenY: Returns the y coordinate of the window relative to the screen
self: Returns the current window
status: Sets the text in the statusbar of a window
top: Returns the topmost browser window

Window Object Methods

alert(): Displays an alert box with a message and an OK button
blur(): Removes focus from the current window
clearInterval(): Clears a timer set with setInterval()
clearTimeout(): Clears a timer set with setTimeout()
close(): Closes the current window
confirm(): Displays a dialog box with a message and an OK and a Cancel button
createPopup(): Creates a pop-up window
focus(): Sets focus to the current window
moveBy(): Moves a window relative to its current position
moveTo(): Moves a window to the specified position
open(): Opens a new browser window
print(): Prints the content of the current window
prompt(): Displays a dialog box that prompts the visitor for input
resizeBy(): Resizes the window by the specified pixels
resizeTo(): Resizes the window to the specified width and height
scroll(): Scrolls the window
scrollBy(): Scrolls the content by the specified number of pixels
scrollTo(): Scrolls the content to the specified coordinates
setInterval(): Calls a function or evaluates an expression at specified intervals (in milliseconds)
setTimeout(): Calls a function or evaluates an expression after a specified number of milliseconds